﻿// Copyright 2004-2011 Castle Project - http://www.castleproject.org/
// 
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// 
//     http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#region 导入名称空间

using System;
using System.Diagnostics;
using System.Reflection.Emit;

#endregion

namespace LightWork.DynamicProxy.Generators.Emitters.SimpleAST
{
    [DebuggerDisplay("{reference} as {type}")]
    public class AsTypeReference : Reference
    {
        private readonly Reference reference;
        private readonly Type type;

        public AsTypeReference(Reference reference, Type type)
        {
            if (reference == null)
                throw new ArgumentNullException("reference");
            if (type == null)
                throw new ArgumentNullException("type");
            this.reference = reference;
            this.type = type;
            if (reference == OwnerReference)
                OwnerReference = null;
        }

        public override void LoadAddressOfReference(ILGenerator gen)
        {
            // NOTE: Or maybe throw new NotSupportedException() ?
            reference.LoadAddressOfReference(gen);
        }

        public override void LoadReference(ILGenerator gen)
        {
            reference.LoadReference(gen);
            gen.Emit(OpCodes.Isinst, type);
        }

        public override void StoreReference(ILGenerator gen)
        {
            // NOTE: Or maybe throw new NotSupportedException() ?
            reference.StoreReference(gen);
        }
    }
}